Esophageal function testing using multichannel intraluminal impedance

Multichannel intraluminal impedance (MII) is a new technique for evaluation of bolus transport. We evaluated esophageal function using bolus transport time (BTT) and contraction wave velocity (CWV) of liquid, semisolid, and s olid boluses. Ten healthy subjects underwent MII swallow evaluation with va rious boluses of sterile water (pH 5), applesauce, three different sized ma rshmallows, and iced and 130 degreesF water. The effect of bethanechol was also studied. There was no difference in BTT or CWV for all water volumes f rom 1 to 20 ml. There was significant linear increase of BTT with progressi vely larger volumes of applesauce, and BTT of applesauce was longer than fo r water. BTT was significantly longer with large marshmallows vs. small and medium and was longer than for water. BTT for iced water was similar to 13 0 degreesF water. Applesauce showed a significant linear decrease of CWV wi th progressively larger volumes and was slower than water. Marshmallow show ed significantly slower CWV with the large vs. small, and CWV for ice water was significantly slower than 130 degreesF water. Therefore, BTT of liquid is constant, whereas BTT of semisolid and solid are volume dependent and l onger than liquids. CWV of semisolids and solids are slower than liquids. C WV of cold liquids is slower than warm liquids. MII can be used as a discri minating test of esophageal function.